Treatment of hydrocarbons



NOV 22, 1938 P. H. SULLIVAN TREATMENT OF HYDROCARBONS Filed Nov. 1B, 1955 2 Sheets-Sheet l BMM M ATTORNEY NOV. 22, 1938.. p. Hl SULLWAN 2,137,825

TREATMENT OF HYDROCABBON S Filed Nog. 1s; 1935 2 sheets-sheen 2 INVENTOR PIKE H.SULLIVAN Bbw@ d# M ATTORNEY Patented Nov. 22, 1938 2,1

UNITED STATES PATENT QFFICE TREATMENT F HYDROCARBONS Pike H. Sullivan, New Rochelle, N. Y., assignor to Gasoline Products Company, Inc., Newark, N. J., a corporation of Delaware Application `imwembaf 1s, 1933, serial No. 698,569 1o claims. (el. 19a-9) 'I'his invention relates to the production of valmy invention. Nor is it always necessary to reuable low-boiling normally liquid hydrocarbon cover as many fractions as there are desired oils, such as motor fuels of high anti-knock value, parains present. For example, I may recover a` from normally gaseous hydrocarbons, and an obfraction consisting largely of ethane, a second 5 ject of my invention is to effect the production in fraction containing propane, and a third frac- 5 an improved and eflicient manner of normally tion containing butane and pentane. In any event liquid hydrocarbons, and especially those boiling the gas fractions are separately and individually within a gasoline or motor-fuel range, from gasesubjected to gasA pyrolysis under preselected conous mixtures containing a plurality of gaseous ditions, as will be described more fully herein paralilns having higher molecular weights than below. 10 methane, for example, ethane, propane, butane In its broadest aspect, my invention is not conand pentane. cerned with the particular manner in which frac- My invention has for further objects such adtionation is effected, and this may be accomditlonal improvements in operative advantages plished in any known suitable manner. In a and results as may hereinafter be found to obpreferred and more specific form, however, the 15 tain. fractionation is accomplished by means of ab- My invention contemplates fractionating or sorbent oil, the absorption and separation of the rectifying a gaseous mixture containing a pluindividual fractions being effected by treating the rality of gaseous paraiiins to separate a plurality gaseous mixture in a plurality of counter-curof gas fractions relatively rich in individual parrent stages with carefully limited iiows of ab- 20 aillns, such as ethane, propane, butane, and pensorbent oil to obtain selective effects. The abtane, the subjection of these gas fractions to insorbed hydrocarbons are then freed from the dividual gas cracking operations under optimum absorbent oil in a corresponding plurality of conditions with respect to the individual parailin stripping stages, preferably by convective disgases for the production of gaseous olefins, and tillation. 25 the subsequent combining of the olelnic prod- I have found that, whereas in the prior art it ucts resulting from the several gas-cracking was customary to treat the several paraffinic stages for subjection to elevated temperature and gases together for the production of olens, the pressure effective to promote polymerization of best results may be obtained by separately and oleiins to normally liquid hydrocarbons. individually treating the several paramnic gases 30 As starting material for my process, I may emvSuch as ethane, propane, butane, and pentane, or ploy any gaseous hydrocarbon mixture containat any rate, gases relatively concentrated in these ing substantial amounts of gaseous paraillns of hYdrOCalbOnS, respectively, under Conditions higher molecular weight than methane. For ex- Varying With respect t0 each Other as t0 temample, I may employ gases produced during the perature, reaction time or both. 35 cracking of petroleum oils or coal gas, and some Thus. the PYIUIYSS 0f Ethan@ iS Preferably C011- natural gases. ducted ata temperature of from 800 to 900 C.;

In order to make it possible to treat several that 0f propane at from 750 to 850 C.; that 0f paraiilnic gases 'such as ethane, propane, butane butane at 700 t0 800 C.; and that 0f pentane at 40 and pentane under optimum conditions, the gas- 650 t0 750 C.. the temperature falling with in- 40 eous mixture is first fractionated or rectified in creasing molecular weight, whereas if these gases order to separate and separately recover fractions are treated together the average temperature relatively rich in the individual parail'in gases; that which will be necessary to be maintained will be is to say, containing the individual parain gases too low to secure the optimum results as regards in relatively pure and isolated form. 'I'heoreticalthe conversion of ethane, and too high to secure 45 ly, if ethane, propane, butane and pentane are the best results with respect to the conversion all present in substantial amounts, these can be of pentane and, butane. recovered in substantially pure form as so many According to my invention therefore the sevindividual gaseous fractions, and reasonable eral gas fractions are separately and individually thoroughness of separation is always to be detreated at atmospheric pressure or moderately 50 sired. In practice, however, recovery of the deelevated pressures not exceeding 200 pounds per sired paraiilnic gases in substantially more consquare inch, and at temperatures within the centrated form is advantageous in any event, and ranges indicated, for periods of time suftlcient to the extent to which the separation is carried may effect substantial degrees of conversion to olebe considerably varied without departing from flnic products, and the resulting olenic gases 55 resulting from the several gas pyrolysis stages are then combined and subjected to pressures of the order of 1000 to 3000 pounds per square inch, or even higher, and temperatures of from 300 to 600 C., although these limits are not absolutely necessarily adhered to, in order to effect a polymerization of normally gaseous oleiins to normally liquid materials.

If desired, the polymerization may be conducted in the presence of hydrocarbon vapors from another source; for example, the products from the cracking or reforming of low boiling hydrocarbon materials such as gasoline or naphtha, may be introduced into the polymerization stage in accordance with the invention set forth in my application Serial No. 661,868 filed March 21, 1933. Or, if desired, other gases and oils may be introduced into the polymerizing chamber or into the stream of gases being delivered thereto, for the purpose of modifying the polymerizlng reactions, or for thepurpose of controlling the temperature conditions during the polymeriza tion stage.

The products resulting from the polymerizing operation are withdrawn and fractionated in conventional manner to recover therefrom normally liquid hydrocarbons, and a portion or all of the remaining gases may be returned to the initial fractionation stage wherein the several gaseous parafllns are separated.

As a rule, the gaseous mixtures which are available for the practice of my invention will contain considerable amounts of hydrogen as well as methane. It has been found that methane ds not respond readily to gas pyrolysis for the production of oleiins, and it is an advantage of my present invention that in the preliminary gas-fractionation stage, hydrogen and methane are largely separated from the higher parafilns, thus avoiding the presence of large quantities of these materials in the gas pyrolysis stages and making possible the recirculation of the gaseous products remaining after the polymerizing stage inthe manner set forth hereinabove.

In order that these and other aspects of my invention may be clearly set forth, I now describe, with reference to the accompanying drawings, a preferred manner in which my invention may be practiced and embodied, but without limiting my invention to such illustrative`V` example or examples as are given hereinbelow. In these drawngs:

Fig. 1 is a more or less diagrammatic elevational view of a system for effecting conversion of gaseous paraflns to normally liquid hydrocarbons in accordance with my present invention; and

Fig. 2 is a similar view of an alternative or more specific form of a portion of the system illustrated in the preceding gure.

Similar reference numerals designate similar parts in both of the views of the drawings. Y

Referring now to the drawings, and more particularly Fig. 1, gases, such as cracking-plant gases, containing ethane and higher gaseous paraflins, are delivered through a conduit I by means of a pump 2, or where possible, under their own pressure, to a fractionating stage 3 of any suitable type and wherein the gases are fractionated or rectified to effect the separation of a desired plurality of fractions constituting, insofar as is possible or desired, the individual gaseous parafns higher than methane in relatively pure form. While in Fig. 1 I have shown four fractions consisting largely of ethane, propane. butane and will be understood that in accordance with the general description of my invention given hereinabove, the number and charactere ofthe various fractions may be varied in accordance with the character of the gases initially treated and the nature of the results desired.

Residual gases such as hydrogen and methane which it is not desired to include in the fractions separated for pyrolysis and polymerization are shown as being withdrawn from the fractionation stage 3 through a conduit 8.'

Assuming that four fractions consisting of ethane, propane, butane, and pentane, respectively, have been withdrawn from the fractionating stage 3 through lines 4, 5, 8 and 1, these are then delivered by means of pumps 9, III, II and I2, if necessary, to a corresponding plurality of gas pyrolysis furnaces Il, I5, I6 and I'I, respectively, where these gaseous fractions are separately and individually treated under optimum temperature conditions ranging from about 650 C. to about 900 C., and preferably under a pressure not exceeding 200 pounds per square inch. In a preferred instance in which four fractions are separated as indicated hereinabove, the specic operating temperatures in the furnaces I4, I5, I6 and I1 may be about 850, 800, '150 and 700 C., respectively.

In addition to varying the temperatures obtaining in the furnaces I4 to I'I the reaction times may likewise be varied. This is especially true where the temperatures obtaining in the various gas pyrolysis furnaces approach each other closely.

In general the times of contact employed in the gas-pyrolysis stage will be relatively short, for example, from one second or even less to three seconds or even as high as five seconds, and for any given gas will tend to decrease with rising temperatures.

Where desired, as for example where the concentration of pentane in the gases being treated is rather low, the furnace I1 may be omitted and the fractionation conducted in such manner as to include whatever pentane is present in the fraction consisting largely of butane, and which is delivered to the furnace I6. In this instance, the temperature maintained in the furnace I6 will preferably be from 700 to 750 C., for example about '725 C. Or, if desired, the pentane and butane fractions may be included with the propane fraction delivered to the furnace I5, in which event furnaces I8 and I'I may both be omitted. The furnace I in this instance will be maintained at a temperature of from 725 to 800 C., for example, about 775 C. It will be understood, however, that when the various fractions are thus combined, the specific operating temperatures will depend not only upon the preferred temperature ranges indicated hereinabove with respect to the individual parafiins but will also depend to a considerable extent upon the proportions of the individual parailins present in the fractions undergoing pyrolysis.

The oleflnic `gases resulting from the pyrolyses taking place in the furnaces I4 to i1 are then combined and passed through a manifold line I8, a branch line I9 having valves 20 and 2|, and a line 22 to a compressor 23, which delivers the gases under a pressure of 1000 to 3000 pounds gr guare inch or higher, to a reaction cham- It is ordinarily desirable to maintain the gases CTI undergoing polymerization in the reaction chamber 24 at a temperature of from 300 to 600 C., and while the chamber 24 may be cooled for this purpose, it is ordinarily preferred to cool the gases in some manner prior to their entry into the chamber 24. This may be accomplished in any one of several manners, for example, by closing the valve 20 and permitting the gases from the furnaces I4 to l1 to pass through a branch line 25, having valves 26 and 21, to a cooler 28. As will .be pointed out more fully in connection with Fig. 2, the cooling taking place in the cooler 28 may be suiiicient to bring the olenic gases down to substantially atmospheric temperature, or merely to the temperature desired to maintain in the chamber 24.

As an alternative method of cooling the gases, hydrocarbon gas or oil from an extraneous source may be introduced by means of a compressor or pump 3| and a line 32 to the inlet side `of the compressor 23 which delivers the gases into the polymerization chamber 24. Various inert or diluent gases as well as reactive hydrocarbon gases, and various oils or tars, may be introduced to the polymerizing chamber as thus indicated.

Naphtha or gasoline of sufliciently low antiknock value to warrant further cracking or reforming of the same may be introduced through a conduit 33 and a pump 34 to a heating coil located within a furnace 35, wherein the naphtha is subjected to cracking or reforming at temperatures of the order of 800 to 1300 F. under pressures of from 150 to 1000 pounds per square inch or higher, and the vaporous products resulting from such cracking or reforming may then be delivered by means of a conduit 36 to the chamber 24, or to the inlet -side of the compressor 23 for delivery to the chambers 24.

In the instance illustrated in Fig. 1 it is assumed that 'the naphtha-reforming operation takes place in the furnace 35 under a pressure at least equal to that obtaining in the polymerizing chamber 24 and where this is true, as shown in the drawings, the products from the furnace 35 may be delivered `directly to the chamber 24. Where, however, the reforming operation is conducted under a lower pressure than that obtaining in the polymerizing chamber 24, the reformed products, with or without cooling, as desired, may be compressed to a pressure at least equal to that obtaining in the polymerizing chamber 24 before being delivered to the latter.

As has been stated hereinabove, the gases are maintained within the chamber 24 for a period of time suiiicient to effect polymerization of normally gaseous materials to normally liquid materials'to a substantial extent. The products are th'en withdrawn from the chamber 24 to a conduit 31, which may be provided with valve 38, and passed to an evaporator or low-pressure chamber 4| located inthe lower portion of a fractionating tower 42 provided with the usual plates or trays 43 and cooling means 44.

Under reduction of pressure and cooling effected in the fractionator 42, liquid products heavier than the desired motor fuel products are condensed .and are withdrawn through valved lines 45 and 46 for disposal in any desired manner, and the lower-boiling hydrocarbon vapors, together with unconverted gases, pass through a. vapor line 41 to a cooler 48, where the normally liquid hydrocarbons useful as motor fuel are condensed. The cooled products are delivered from the cooler 48 through a line 49 to a gas separator 50, from which the motor-fuel condensate is withdrawn through a conduit having a valve 52. The residual gases may be withdrawn from \the system through a line 53 having a valve 54,

or a portion or all of these gases may be returned through a line 55 having valves 56 and 51 to the inlet side of the pump 2 or directly to the fractionating stage 3. These gases will consist largely of methane, together with some hydrogen and considerable quantities of parafiinic and olelnic gases, and may advantageously be recirculated in view of the removal of methane and hydrogen in the fractionating stage 3.

In the instance illustrated in Figure 2, the preliminary fractionation of the paraiinic gases is accomplished in a plurality of absorption stages located in series in the path of the gases and wherein the gases are scrubbed with a solvent or solvents introduced in regulated` quantities to give selective effects as regards the several paraiin constituents.

Referring to the figure, the fractionator 3 in this instance comprises a plurality of absorber sections 6|, 62 and 63, through which the gas travels in the reverse order and in which the gases are successively subjected to countercurrent contact with a plurality of iiows of absorbent oil or oils introduced into the absorbing sections in regulated amounts.

In the present instance, the introduction of absorbent oil into the section 63 is regulated to effect an absorption of butane and pentane to as complete an extent as possible without effecting any considerable absorption of parainic constituents of lower molecular weight. The introduction of absorbent oil to the section 62 is regulated to eilect a selective absorption of propane, and the introduction of oil to the section 6| to eifect a selective absorption of ethane, While hydrogen and methane and other residual gases pass out of the fractionator 3 through the conduit 8. It will be understood that with reference to both this figure and the preceding figure. oleinic constituents present in the gas (such as ethylene, propylene and butylene) will normally be absorbed together with the paraiflnic constituents more nearly related thereto, respectively.

'I'he enriched absorbents pass out of the sections 6|, 62 and 63 through lines 64, 65 and 66 to corresponding heat exchangers 61, 68 and 69, and thence through lines 1li,v 1| and 12 to stripping stills 13, 14 and 15, respectively. If desired, preheaters (not shown) may be inserted in the lines 10, 1| and 12 for the purpose of iml parting additional heat to the enriched absorbents.

In the stripping stills 13, 14 and 15,'which are supplied with steam from lines 16, the absorbents are stripped of their respective contents of paraflinic gases. The latter pass off in vapor form with the steam, and the stripped absorbents then pass through lines 18, 19 and 80, wherein are located pumps 8|, 82 and 83, respectively, through heat exchangers 61, 68 and 69, lines 84, 85 and 86, coolers 81, 88 and 89 and lines 90, 9| and 92 to the absorbing sections 6|, 62 and 63, respectively, thus completing their respective cycles.

The vapors liberated in the stripping stills 13, 14 and 15, which (in addition to steam) contain ethane, propane and a mixture of butane and pentane, respectively, pass through vapor lines 93, 94 and 95 to condensers 96, 91 and 98 and water separators |0I, |82 and |03. The gas fractions then pass through lines |04, |05 and |06,

wherein are located pumps |0'I, |08 and |09, to the gas pyrolysis furnaces I4, I5 and I6.

In the present instance, as has been indicated hereinabove, the ethane fraction passing through the furnace Il is brought to a temperature of 800 to 900 C. The propane fraction 4passing through the furnace I5 is brought to a temperature of from 750 to 850 C. while the mixture of butane and pentane passing through the furnace I6 is carried to a temperature of from '700 to '150 C., all of these fractions being maintained at the indicated temperatures for sumcient time to effect the desired conversion to oleiins.

The olefinic gases from the furnaces I4, I5 and I6 are then combined in the manifold line I8 and pass to the cooler 28 where, in the present instance, they are cooled to substantially atmospheric temperature. The products then pass to a separator II I, from which any normally liquid material may be removed through a valved line II2, while the oieilnic gases pass through a conduit II3 having a pump III to a coil IIB located within a suitable furnace II8 and wherein the gases are brought to a temperature of from 30D-600 C. under a pressure in excess of 1000 pounds per square inch, to effect polymerization of gaseous olens to normally liquid materials.

The products o! polymerization leave the furnace IIB through a line II1 having a valve ||8. If the time of contact retained in the heating coil IIB is not suilicient or if further reaction is desired for any other reason, these products may be delivered to a polymerizing chamber such as the chamber of Fig. 1. Otherwise, the products are delivered through line II1 to the usual Ature and separation of the desired liquid products, all or a portion of the gases may be returned to some earlier point in the system, for

l' fins having more than one carbon atom in rela- It will be `understood by those skilled in the art fins from the absorbent, separately and individexample to the fractionatlng tower 3.

that the various features of operation described in connection with the two iigures are not necessarily limited to the specific examples in connection with which they have been described. For

example, condensation to atmospheric temperatures in the cooler 2l and the use oi a coil furnace such as the furnace IIB may be employed in conjunction with the apparatus illustrated in Fig. l, and various other features of the two illustrative examples may be combined as de` sired.

While, in the illustrative examples given hereinabove, I have described several gas pyrolysis operations as being effected in furnaces oi.' the for the production of oil gas and carburetted water gas.

As a further extension of my invention, the gaseous fraction removed from the fractionating stage 3, which comprises residual constituents such as methane and hydrogen, if sufficiently high in methane content may be subjected to more drastic temperature conditions, for example, 1200 C. or higher, for the purpose of reforming the same, that is to say, for the purpose of effecting the breaking down of methane to hydrogen and carbon. The thereby re-formed gas may then be employed for use as a fuel gas or for any other purpose, for example, as a source of hydrogen.

With further reference to the specific example illustrated in Fig. 2, it will be obvious to those skilled in the art that the absorbent oil or oils employed in the sections BI, 62 and 83 may comprise any of the hydrocarbon oils commonly employed for absorption purposes. Such oils should possess suiilcient fluidity to enable easy handling and boiling-point ranges suiilcientiy high to preventl substantial volatilization in the stripping stills. As an example of such an oil, gas oil boiling between 450 F. and 600 F. may be cited. While I have indicated that the oil employed in s 'ctions 8|, 62 and 63 may be different in character, ordinarily this is unnecessary as it is possible to obtain sufficiently selective results for most purposes by using the same oil in carefully regulated amounts, so that in each section only the higher paraffin or paramns are absorbed to the exclusion insofar as possible of lower parafns.

While I have described my invention hereinabove with respect to several illustrative examples, it will be understood by those skilled in the art that my invention is not limited to the details of these examples except as specifically set forth in the claims hereinafter made.

I claim:

1. The process of obtaining valuable liquid hydrocarbons, which comprises intimately contacting a hydrocarbon mixture containing gaseous paramns with liquid absorbent to separately and selectively absorb individual gaseous paraftively pure states, recovering said gaseous parafually subjecting said gaseous parafiins to pyrolysis under conditions of temperature and pressure adapted to produce optimum quantities of oleiins together with normally liquid hydrocarbons therefrom, separating normally liquid hydrocarbons normally liquid hydrocarbons therefrom.

2. 'I'he process of obtaining valuable liquid hydrocarbons from a hydrocarbon mixture containing gaseous parailins, which comprises intimately contactlng said mixture with liquid absorbent to separately and selectively absorb individual gaseous paraflins having more than one carbon atom in relatively pure states, recovering said gaseous parafiins from the absorbent, separately and individually subjecting said gaseous paraffins to pyrolysis under conditions of temliquid hydrocarbons therefrom, combining olednic gases and normally liquid hydrocarbons resulting from said pyrolyses, separating said normally liquid hydrocarbons from said olelnic gases, subjecting other hydrocarbon fluid to a conversion operation, admixing products of conversion therefrom'with said separated olefinic gases, subjecting the olefinic gases and admixed hydrocarbon fiuid to conditions of high pressure and elevated temperature effective to promote polymerization of olefins to higher boiling products, and vfractionating the resultant products to recover normally liquid hydrocarbons therefrom.

3. The process of obtaining valuable liquid hydrocarbons from a hydrocarbon mixture containing gaseous paraihns, which comprises intimately contacting said mixture with liquid absorbent to separately and selectively absorb individual gaseo'us paraiiins having more than one carbon atom in relatively pure states, recovering said gaseous parafiins from the absorbent, separately and individually subjecting said gaseous paramns to pyrolysis under conditionsof temperature and pressure adapted to produce optimum quantities of olens together with normally liquid hydrocarbons therefrom, combining olefinic gases and normally liquid hydrocarbons resulting from said pyrolyses, separating said normally liquid hydrocarbons from said olefinic gases, subjecting other hydrocarbon fluid to a conversion operation, admixing products of conversion therefrom with said separated olefinic gases, subjecting the olefinic gases and admixed hydrocarbon fiuid to conditions of high pressure and elevated temperature effective to promote polymerization of oleflns to higher boiling products, fractionating the resultant products to recover normally liquid products therefrom, and returning the remaining gases to said contacting stage.

4. The process of obtaining valuable liquid hydrocarbons from a hydrocarbon mixture containing gaseous parafiins, which comprises intimately contacting said mixture with liquid absorbent to separately and selectively absorb ethane and propane in substantially pure states, recovering said ethane and propane from the absorbent, separately and individually subjecting said ethane and propane to pyrolysis under conditions of temperature and pressure adapted to produce optimum quantities of oleflns together with normally liquid hydrocarbons therefrom, combining olenic gases and normally liquid hydrocarbons resulting from saldpyrolyses, separating said normally liquid hydrocarbons from said olefinic gases, subjecting other hydrocarbon fluid to a conversion operation, admixing products of conversion therefrom with said separated olefnic gases, subjecting the olefinic gases and admixed hydrocarbon fluid to conditions of highl pressure and elevated temperature effective to promote polymerization of olefins to higher boiling products, and fractionating the resultant products to recover normally liquid hydrocarbons therefrom.

5. The process of obtaining valuable liquid hydrocarbons from a hydrocarbon mixture containing gaseous parafllns, which comprises intimately contacting said mixture with liquid absorbent to separately and selectively absorb ethane, propane and butane in substantially pure states, recovering said ethane, propane and butane from the absorbent, separately and individually subjecting said ethane, propane and butane to pyrolysis under conditions of temperature and pressure adapted to produce optimum quantities of olens together withy normally liquid hydrocarbons therefrom, combining olefinic gases and normally liquid hydrocarbons resulting from said pyrolyses, separating said normally liquid hydrocarbons from said olenic gases, subjecting other hydrocarbon iuid to a conversion operation, admixing products of conversion therefrom with said separated oleflnic gases, subjecting the olefinic gases and admixed hydrocarbon uid to conditions of high pressure and elevated temperature effective to promote polymerization of olefins to higher boiling products, and fractionating the resultant products to recover normally liquid hydrocarbons therefrom.-

6. The process of obtaining valuable liquid hydrocarbons from a hydrocarbon mixture containing ethane and propane, which comprises intimately contacting said mixture With liquid absorbent to separately and selectively absorb ethane and propane in relatively pure states, recovering said ethane and propane from the absorbent, separately subjecting said ethane -and said propane to a temperature of from 800 to 900 C. and a temperature of from 750 to 850 C., respectively, under pressures of not more than 200 pounds per square inch to produce olens and normally liquid hydrocarbons therefrom, combining olefinic gases and normally liquid hydrocarbons resulting therefrom, separating said normally liquid hydrocarbons from said olefinic gases, subjecting other hydrocarbon fiuid to a conversion operation, admlxing products of conversion therefrom with said separated oleinic gases, subjecting the olenic gases and admixed hydrocarbon fluid to a temperature of from 300 to 600 C. under a pressure of at least 1000 pounds per square inch to effect polymerization of olefins to higher boiling products, and fraotionating the resultant products to recover normally liquid hydrocarbons therefrom.

7. The process of obtaining valuable liquid hydrocarbons from a hydrocarbon mixture containing ethane, propane and butane which comprises intimately contacting said mixture with liquid absorbent to separately and selectively absorb ethane, propane and butane in relatively pure states, recovering said ethane, propane and butane from the absorbent, separately subjecting said ethane, said propane and said butane to a temperature of from 800 to 900 C., a temperature of from 750 to 850 C. and a temperature of from 700 to 800 C., respectively, under pressures of not more than 200 pounds per square inch to produce olefins and normally liquid hydrocarbons therefrom, combining the olenic gases and normally liquid hydrocarbons resulting therefrom, separating said normally liquid hydrocarbons from said olenic gases, subjecting other hydrocarbon fluid to a conversion operation, admixing products of conversion therefrom with said separated oleiinic gases, and subjecting the olenic gases and admixed hydrocarbon fluid to a temperature of from 300 to 600 pounds per square inch to effect polymerization of oleflns to higher boiling products, and fractionating the resultant products to recover normally liquid hydrocarbons therefrom.

8. The process of obtaining valuable liquid hydrocarbons from a hydrocarbon mixture containing gaseous parafllns, which comprises fractionating said mixture to separate individual gaseous parafiins having more than one carbon atom in relatively pure states, separately and individually subjecting said gaseous parafiins to conditions of temperature and pressure adapted to produce optimum quantities of olefins together with normally liquid hydrocarbons therefrom,

C. under a pressure of at' least 1000 combining olellnic gases and normally liquid hydrocarbons resulting therefrom, separating said normally liquid hydrocarbons from said oleflnic gases, subjecting other hydrocarbon uid to a conversion operation, admixing products of conversion therefrom with said separated olellnic gases, subjecting the oleflnic gases and admixed hydrocarbon fluid to conditions of high pressure and elevated temperature to effect polymerization\of oleilns to higher boiling products, and fractionating the resultant products to recover normally liquid hydrocarbons therefrom.

9. The process of obtaining valuable liquid hydrocarbons from a hydrocarbon mixture containing gaseous paramns, which comprises fractionating said mixture to separate individual gaseous parailins having more than one carbon atom in relatively pure states. separately and individually subjecting said gaseous parafllns to conditions of temperature and pressure adapted to produce optimum quantities of olens together with normally liquid hydrocarbons therefrom, combining oleilnic gases and normally liquid hydrocarbons resulting therefrom, separating said normally liquid hydrocarbons from said oleiinic gases. subjecting the olenic gases to conditions of high pressure and elevated temperature in the presence of naphtha added to said gases and extraneously heated to an elevated conversion temperature and undergoing conversion to effect polymerization of oleflns to higher boiling products, and fractionating the resultant products to recover normally liquid hydrocarbons therefrom.

10. The process of obtaining valuable liquid hydrocarbons from a hydrocarbon mixture containing gaseous paraillns, which comprises fractionating said mixture to separate individual gaseous paraiilns having more than one carbon atom in relatively pure states, separately and individually subjecting said gaseous paraflins to conditions of temperature and pressure adapted to produce optimum quantities of olens together with normally liquid hydrocarbons therefrom, combining oleilnic gases and normally liquid hydrocarbons resulting therefrom, separating said normally liquid hydrocarbons from said oleilnic gases, subjecting the oleilnic gases to conditions of high pressure and elevated temperature to eiIect polymerization of oleflns to higher boiling products, separately heating naphtha to a temperature sufllcient to effect reformation thereof, combining naphtha thus heated with oleinic gases undergoing polymerization. and fractionating the resultant products to recover normally liquid hydrocarbons therefrom.

PIKE H. SULLIVAN 

